Geometrical calibration of an AOTF hyper-spectral imaging system

Žiga Špiclin; Jaka Katrašnik; Miran Bürmen; Franjo Pernuš; Boštjan Likar

doi:10.1117/12.841727

23 February 2010 Geometrical calibration of an AOTF hyper-spectral imaging system

Žiga Špiclin, Jaka Katrašnik, Miran Bürmen, Franjo Pernuš, Boštjan Likar

Proceedings Volume 7556, Design and Quality for Biomedical Technologies III; 75560I (2010) https://doi.org/10.1117/12.841727
Event: SPIE BiOS, 2010, San Francisco, California, United States

Abstract

Optical aberrations present an important problem in optical measurements. Geometrical calibration of an imaging system is therefore of the utmost importance for achieving accurate optical measurements. In hyper-spectral imaging systems, the problem of optical aberrations is even more pronounced because optical aberrations are wavelength dependent. Geometrical calibration must therefore be performed over the entire spectral range of the hyper-spectral imaging system, which is usually far greater than that of the visible light spectrum. This problem is especially adverse in AOTF (Acousto- Optic Tunable Filter) hyper-spectral imaging systems, as the diffraction of light in AOTF filters is dependent on both wavelength and angle of incidence. Geometrical calibration of hyper-spectral imaging system was performed by stable caliber of known dimensions, which was imaged at different wavelengths over the entire spectral range. The acquired images were then automatically registered to the caliber model by both parametric and nonparametric transformation based on B-splines and by minimizing normalized correlation coefficient. The calibration method was tested on an AOTF hyper-spectral imaging system in the near infrared spectral range. The results indicated substantial wavelength dependent optical aberration that is especially pronounced in the spectral range closer to the infrared part of the spectrum. The calibration method was able to accurately characterize the aberrations and produce transformations for efficient sub-pixel geometrical calibration over the entire spectral range, finally yielding better spatial resolution of hyperspectral imaging system.

Citation Download Citation

Žiga Špiclin, Jaka Katrašnik, Miran Bürmen, Franjo Pernuš, and Boštjan Likar "Geometrical calibration of an AOTF hyper-spectral imaging system", Proc. SPIE 7556, Design and Quality for Biomedical Technologies III, 75560I (23 February 2010); https://doi.org/10.1117/12.841727

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available